JWT Decoder & Encoder

Decode, verify, and create JSON Web Tokens. Supports HS256 signature algorithm.

JWT Token

About JSON Web Tokens (JWT)

JWT (JSON Web Token) is an open standard (RFC 7519) for securely transmitting information between parties as a JSON object. JWTs are commonly used for authentication and information exchange in web applications.

Features

  • Decode any JWT token to view its header and payload
  • Verify HS256 signatures with your secret key
  • Validate standard claims (exp, iat, nbf, iss, sub, aud, jti)
  • Check token expiration status with human-readable dates
  • Generate new JWT tokens with HS256 signing
  • Client-side processing - your tokens and secrets never leave your browser

JWT Structure

A JWT consists of three parts separated by dots:

  • Header - Contains the token type and signing algorithm
  • Payload - Contains the claims (data) about the user or entity
  • Signature - Ensures the token hasn't been tampered with